I have a Galco High-Ride concealment holster for my SP-101, I like it. Keeps it tucked close, but with any OWB holster, you need a jacket or untucked shirt.
I've used a Mitch Rosen "Workman" holster for my SP-101 for a couple years now and have been very satisfied with it. I had tried an Uncle Mikes and a Bianchi Accumold and was not happy w/ either. Take at look at Mitch's gear!